1. Field of the Invention
The present invention relates to an apparatus for controlling the distribution of driver power in a motor vehicle which has a pair of torque transmission clutches for varying the torques to be transmitted to respective drive wheels.
2. Description of the Relevant Art
There is known a drive power distribution control apparatus which includes, instead of a mechanical differential, torque transmission clutches such as hydraulically operated multiple-disc clutches for varying the torques to be transmitted a pair of laterally spaced rear drive wheels of a motor vehicle.
When the motor vehicle with such a drive power distribution control apparatus is running straight, it is necessary to apply a uniform hydraulic pressure to the torque transmission clutches for the drive wheels in order to transmit equal torques from a power source such as an engine to the drive wheels. Therefore, pressure regulating valves disposed in respective regulated pressure passages leading to the torque transmission clutches are required to be machined with high precision. Actually, however, it is highly difficult to machine the pressure regulating valves with a required degree of precision. As a result, it is actually difficult to apply equal hydraulic pressures to the torque transmission clutches, and hence the torque generated by the power source cannot efficiently be transmitted to the rear drive wheels.
The present invention has been made in an effort to effectively solve the aforesaid problems of the conventional drive power distribution control apparatus.